Valid structured data and useful structured data are different questions
Free, two permissions, and it makes no network calls at all.
Google's own testing tool will tell you your markup is valid. That is a real answer to a question almost nobody is asking. What you actually want to know is whether you get the stars in the search result, and valid markup frequently does not.
So this reads every piece of structured data on the page, JSON-LD, Microdata and RDFa, and tells you whether you qualify. Which fields are genuinely required versus merely present, and which optional one would upgrade what you get.
It also tells you when you are wasting your afternoon. Google retired FAQ rich results for most sites, so a perfectly valid FAQPage block earns you nothing now. Every validator on earth will still give it a green tick. I would rather tell you before you build forty more of them.
The short version
Schema Markup Validator answers the question you actually had, which is whether Google will show the stars.
- Read every JSON-LD, Microdata and RDFa block on the page and find out whether you actually earn the rich result.
- Find out which of your fields Google genuinely requires, and the one optional addition that would upgrade the result.
- Get told when the whole thing is a waste of an afternoon, like the FAQ blocks Google quietly stopped showing for most sites.
Best for: anyone who has been told their markup is valid and still has no stars in the search result.
Replaces: Google's Rich Results Test for the day-to-day check, when you want an answer without leaving the page.
How to use it
- Open the page.
- Click the icon.
- Read the plain-English summary of each item it found.
- Check the verdict line, which is the bit that says whether this qualifies for a rich result and what is missing if it does not.
Plain English instead of a tree view
Most validators show you your own JSON back, prettier, in a collapsible tree. You wrote it. You know what is in it. What you cannot see at speed is whether it says what you meant.
So every item gets a one-line summary of what it actually is. Something like a Product called Blue Widget at 24.99 with 4.6 stars from 213 reviews. If that sentence is wrong, your markup is wrong, and you spotted it in a second rather than by reading nested braces.
What it can access, and why
| Permission | Why it needs it |
|---|---|
| Reads the current tab | Only when you click the icon. This is the entire function. |
| Runs a script on that tab | To pull the structured data out of the page after JavaScript has finished, since a lot of it is injected rather than in the source. |
Full detail in the privacy policy.
The things people ask before installing
How is this different from the official test? Google's tool answers whether the syntax parses. This answers whether you qualify, which is the question you had. Both are useful and they are not the same question.
Does it phone home? Not once. It makes zero network calls, which you can check yourself by opening the network tab while it runs. Everything it needs is already on the page.
What if my markup is injected by JavaScript? It reads the page as it stands in front of you, so anything your tag manager or framework injected is already there and gets checked with the rest.
Free, and it stays free. No account, no sign-up, and nothing leaves your browser.
FAQ
Does it find markup added by JavaScript?
Yes, and this is the main reason to use an extension rather than a source viewer. It reads the page after scripts have run, so tag-manager-injected and framework-rendered markup both show up. Anything that only exists in your server HTML but gets overwritten by JavaScript will also be visible as the overwritten version, which is the version Google sees.
Why does it say my valid markup will not get a rich result?
Usually one of three reasons. A required field is missing, or you have used a type Google no longer rewards, or the markup describes something the page itself does not clearly show. That last one is a real rule and not a technicality. Markup has to reflect visible content, so a review rating in your JSON with no reviews on the page is a policy problem rather than a syntax one.
Is this a replacement for Google Search Console?
No, and it cannot be. Search Console tells you what Google actually did with your pages after crawling them, which is the truth. This tells you what is on a page right now, instantly, before you deploy. Use this while working and Search Console to confirm.
Does it support every schema.org type?
It reads all of them, and it has specific rich-result rules for the types Google documents rewards for. For an obscure type you will see the data parsed and summarised but no qualification verdict, because there is no rich result to qualify for.